Neptune, at about 165 Earth years.
Jupiter takes 11.86 Earth years to orbit the Sun - this is the 4th longest orbital period.
Each planet in the solar system has a different orbital period, corresponding to the different sizes of their elliptical orbits.For the Earth, the present orbital period is 365.25636days. (rounded)
In our solar system Neptune is the planet with the longest period or year - equal to about 165 Earth years.
Mercury is the planet that orbits the sun every 165 days. It is the closest planet to the sun in our solar system and has the shortest orbital period.
It would depend on the star it was orbiting. If it were in our solar system, its orbital period would be little more than 30 years. (Saturn is approximately 9.5 AU from the Sun.)
A "year" on earth turned out to be the period of the earth's orbital revolution around the sun, although the word was invented long before any knowledge of the structure of the solar system or the earth's place in it. By analogy, the same word is typically used to refer to the period of orbital revolution of any other planet.
Mercury is the fastest orbiting planet in the inner Solar System, with an average orbital velocity of 47.87 km/s.
If you still consider Pluto to be a planet, then the answer is Pluto, which completes one revolution around the sun in 248 years. If you agree with the downgrading of Pluto to something less than a full-fledged planet, then the answer is Neptune. The general rule is: The farther a planet is from the sun on the average, the longer it takes to complete its orbital revolution.
There are no planets in our solar system with a rotational period of 318 days. The longest is Venus, with a rotational period of 243 days.
From among the objects discovered so far, that would be the planet Mercury with a period of orbital revolution of 88 earth days.Anything with a shorter orbital period would have to spend most of its time closer to the sun than Mercury is.
Mercury.
No planet in the solar system has a longer orbit than Jupiter. Jupiter has the longest orbital period, taking approximately 11.9 Earth years to complete one orbit around the Sun.